In French version of the game:
. Both in Craft and Inventory windows, in up-right corner the close cross shows ?[UI_inventory_action_return_to_game] in bottom tooltip, instead of "Retourner jouer" (or "Retour au jeu").
. More, in Inventory window, the up-right close cross is shifted to the right, so it's quite hidden out of the screen (but we still can use it).

I verified in English version: here that's good, close crosses show 'Return to game' in tooltip, and the one cross in inventory is well set (like in craft window).